• 한국결정성장학회지
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• 제17권6호
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• pp.277-282
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• 2007

화력발전소에서 발생하는 석탄 바닥재(bottom ash)와 점토를 혼합하여 성형 후, 소성하여 인공경량골재를 제조하고, 소성온도와 조성 변화에 따른 물성을 분석하였다. 바닥재는 입경이 4.75mm 이상인 입자가 13wt% 정도로 거친 분말로 압출성형을 위하여 미분쇄 공정이 필요하였다. 또한 바닥재는 미연탄소(C)를 다량 함유하고 있어 소결 시 C의 산화반응과 이에 따른 가스발생으로 소결체의 경량화를 유도하였다. 점토에 바닥재 첨가량이 증가할수록 소성 지수가 감소하였고 이에 따라 성형체의 성형성이 저하되었으나 바닥재 첨가량이 40wt% 까지의 성형체는 소성 지수 및 소성 한계값이 각각 약 10과 22로서 압출성형이 가능하였다. 바닥재가 $30{\sim}50wt%$ 첨가되고 $1150{\sim}1200^{\circ}C$ 범위에서 소결된 골재는 부피비중 $1.3{\sim}1.5$, 흡수율 $14{\sim}16%$를 나타냈고 따라서 고층빌딩이나 교량 등의 골재대체재로써의 가능성이 확인되었다.

• 한국환경농학회지
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• 제41권3호
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• pp.185-190
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• 2022

BACKGROUND: Most of the bottom ash(BA) from wood pellet-based thermal power plants that is not recycled is placed into landfill. BA has a function and structure similar to biochar. Hence, BA is classified as waste, but, it is predicted that BA can be used agricultural utilization. METHODS AND RESULTS: To investigate the effect of BA application on lettuce, growth characteristics and Pb contents were examined with BA application levels(0, 1, 2, 3 and 4 g/L), respectively, in hydroponic cultivation with Pb solution. Irrespective with BA application levels, the length, leaf number and fresh weight of lettuce in BA treatments were increased by 84.3~120, 36.2~39.0, and 215~322%, respectively, compared to the BA-0 treatment. The groups with BA treatments, Pb in the nutrient solution was adsorbed to the BA due to the surface area and functional groups of the BA, and the lettuce growth was maintained more smoothly than in the BA-0 treatment. BA application is considered to have created a favorable environment for lettuce growth in hydroponic cultivation with Pb solution. CONCLUSION(S): Although direct comparing the removal effect of heavy metal between BA and biochar is not present, the BA application in contaminated area suggested a significant meaning on the recycling waste, and increasing potential crop productivity by immobilizing heavy metal.

• 한국농공학회논문집
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• 제55권3호
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• pp.129-140
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• 2013

Bottom Ash is industrial by-product from a thermoelectric power plant. An immense quantities of bottom ash have increased each year, but most of them is reclaimed in ash landfill. In this study, in order to raise recycling rate of Bottom Ash, it is suggested to cure Bottom Ash (BA) mixtures mixed with cement, lime, Fly Ash (FA), and oyster shell (OS). Mixtures of 5~20 % mixing ratio had been cured for 1, 3, 7, 14, and 28 days using sealed curing and air-dry curing method. Unconfined compressive strength test was conducted to determine strength and deformation modulus ($E_{50}$) change for mixtures as mixing ratio and curing day, water contents of mixtures were measured after test. As a result, strength and $E_{50}$ were increased as mixing ratio and curing days, but values and tendencies of them appeared in different as kind of mixture, mixing ratio, curing method, and curing days. The results showed the addition of cement, lime, Fly Ash, and oyster soil in Bottom Ash could improved strength and $E_{50}$ and enlarge its field of being used.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1032-1039
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• 2010

Based on the proven feasibility of bottom ash and tire shred-soil mixtures as lightweight fill materials, tire shred-bottom ash mixtures were suggested as a new lightweight fill material to replace the conventional construction material with bottom ash. Therefore, we carried out the laboratory test, field compaction test and performance test of large scale embankment in order to evaluate their suitability for the use of lightweight fill materials in the before studies. We could verified that the ash, tire-shred and the mixture are able to be the useful materials as light fill materials. In this study, we built real scale embankment with RBA(Reclamated Bottom Ash), TRBA(Tire shred-Reclamated Bottom Ash mixture), WS(Weathered Soil), BA(Bottom Ash screened by 5mm sieve) for monitoring the behavior such as settlement, lateral displacement and water content change. Furthermore, we are examining the ground water quality in the surrounding area of the test embankment.

• 한국건축시공학회지
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• 제9권3호
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• pp.73-78
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• 2009

Coal ash is a by-product of the combustion of pulverized coal, and much of this is dumped in landfills. The disposal of coal ash is one of the major issues for environmental problems. In this paper, the effects of the kinds and replacement ratio of coal ash on the durabilities of concrete mixtures are investigated. Fine aggregate was replaced with coal ash(fly ash and bottom ash) in five different ratios, of 0%, 10%, 20%, 35%, and 50% by volume. Test results indicated that the compressive strength increased with the increase in fly ash percentage. The loss of compressive strength of bottom ash concrete mixes after immersion in sulphuric acid solution was less than in the control mix(BA0). In addition, the carbonation depth of fly ash concrete mixes was lower than the control mix(FA0).

• 한국환경농학회지
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• 제38권4호
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• pp.245-253
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• 2019

BACKGROUND: Weathering of bottom ash (BA) might induce change of its surface texture and pH and affect physical and chemical properties of soil associated with greenhouse gas emission, when it is applied to the arable soil. This study was conducted to determine effect of weathering of BA in mitigating emission of greenhouse gases from upland soil. METHODS AND RESULTS: In a field experiment, methane (CH₄), carbon dioxide (CO₂), and nitrous oxide (N₂O) emitted from the soil was periodically monitored using closed chamber. Three month-weathered BA and non-weathered BA were applied to an upland soil at the rates of 0, 200 Mg ha^-1. Maize (Zea mays L.) was grown from July 1_st to Oct 8_th in 2018. Both BAs did not affect cumulative CH₄ emission. Cumulative CO₂ emission were 23.1, 19.8, and 18.8 Mg/ha/100days and cumulative N₂O emission were 35.8, 20.9, and 17.7 kg/ha/100days for the control, non-weathered BA, and weathered BA, respectively. Weathering of BA did not decrease emission of greenhouse gases significantly, compared to the weathered BA in this study. In addition, both BAs did not decrease biomass yields of maize. CONCLUSION: BA might be a good soil amendment to mitigate emissions of CO₂ and N₂O from arable soil without adverse effect on crop productivity.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.183-184
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• 2020

This study evaluated the effect of foam volume ratio on shear friction behavior of bottom ash based lightweight aggregate concrete (LWA_BA). The LWA_BA with different foam volume ratio ranged between 8 and 25 MPa for compressive strength(f_ck), 17.3~62.5 kN for shear capacity at first shear crack(V_cr), 31.1~73.8 kN for shear friction capacity(V_n), and 0.01~0.03 mm for slip at maximum peak load(S₀). f_ck decreased with increase in the foam volume ratio, showing that this trend was also observed in V_cr, V_n, and S₀.

• 한국환경농학회지
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• 제41권4호
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• pp.252-260
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• 2022

BACKGROUND: The number of biomass power plants is increasing around the world and the amount of wastes from power plants is expected to increase. But the bottom ash (BA) is not recycled and has been dumped in landfill. This study was conducted to find out functional groups of BA and adsorption rate of heavy metals on BA. METHODS AND RESULTS: The BA was dried in oven at 105℃ for 24 hours, and characterized by analyzing the chemistry, functional group, and surface area. The adsorption rates of heavy metals on BA were evaluated by different concentration, time, and pH. As a result, the adsorption amount of the heavy metals was high in the order of Zn> Cu> Cd> Ni and the removal rates of Zn, Cu, Cd, and Ni by BA was 49.75, 30.20, 32.46, and 36.10%, respectively. Also, the maximum adsorption capacity of BA was different by the heavy metal in the environmental conditions, and it was suggested that the isotherms for Zn, Ni, Cd, and Cu were adequate to Langmuir model. CONCLUSION(S): It is suggested that it would be effective to remove heavy metals in aqueous solution by using BA from biomass power plants in South Korea.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.685-688
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• 2008

최근 들어 석탄회의 재활용에 관한 연구는 환경문제와 관련되어 활발히 진행되어 왔으며 미국, 일본과 같은 선진국에서는 이미 석탄회를 각종 산업분야에 적용함으로써 환경오염 저감 및 경제적 이익 측면에서 상당한 성과를 이루고 있다. 이에 국내에서도 지속적인 연구개발을 통해 시멘트 및 레미콘분야 등에서 시멘트 클링커 원료나 콘크리트 혼합재로 석탄회를 사용함으로써 2005년도 기준 전체 석탄회 발생량 중 약 58.5%정도를 재활용하고 있다. 그러나, 이는 석탄회 중 플라이애시(Fly Ash)에 한정된 것으로, 전체 석탄회 발생량 중 10$^{\sim}$20%에 달하는 바텀애시(Bottom Ash)에 대한 재활용은 극히 미미한 실정이며, 현대 대부분 매립처분되어 심각한 환경오염을 야기하고 있다. 이에 본 연구에서는 국가적인 사회간접자본의 투자가 증대됨에 따라 초고강도콘크리트 및 매스콘크리트와 같은 특수콘크리트에 수요가 증대되고 있는 저발열 혼합시멘트(Low Heat-Blended Cement)의 혼합재로써 바텀애시의 사용 가능성 여부를 검토하고자 바텀애시의 첨가량 변화에 따른 저발열 혼합시멘트 및 콘크리트의 기초물성 변화를 비교검토 하였다.

• Architectural research
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• 제4권1호
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• pp.39-44
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• 2002

Recently, the coal-ash production has been increased by increase of consumption of electric power. So it is important to secure a reclaimed land from pollution and develop practical application of coal ash. This is an experimental study to compare and analyze the properties of concrete using high volume of coal ash (including fly ash and bottom ash) as a part of fine aggregate. For this purpose, the mix proportions of concrete according to replacement ratio of coal ash (10, 20, 35, 50%) were selected. And then air content, slump, setting time, bleeding content, chloride content, compressive strength and carbonation test were performed. According to test results, it was found that the bleeding content of concrete using the coal ash decreased according to increase of replacement ratio. And the chloride content of concrete using the bottom ash as a part of fine aggregate increased as the replacement ratio of bottom ash increased, but it is satisfied with the total chloride content of concrete recommended by KCI - $0.3kg/m^3$ below. Also, the compressive strength of concrete using the bottom ash was similar to that of plain concrete(BA 0) after 28days of curing and the carbonation depth of concrete increased as the replacement ratio increased. However, the carbonation depth of concrete using the fly ash decreased as the replacement ratio of fly ash increased.